Nabriva Commences Exclusive Distribution of SIVEXTRO® (tedizolid phosphate) in the U.S.

– SIVEXTRO now available under Nabriva’s National Drug Code

– 100% of SIVEXTRO’s net product sales to be recorded by Nabriva

DUBLIN, Ireland and FORT WASHINGTON, Pa., April 15, 2021 (GLOBE NEWSWIRE) — Nabriva Therapeutics plc (NASDAQ: NBRV), a biopharmaceutical company engaged in the commercialization and development of innovative anti-infective agents to treat serious infections, today announced that it has begun exclusive distribution of SIVEXTRO^® (tedizolid phosphate) in the United States.

SIVEXTRO is now listed in the National Drug Code (NDC) Directory under the Nabriva label. Since April 12, 2021, Nabriva has been marketing and distributing SIVEXTRO in the United States and certain of its territories as part of an exclusive agreement signed in July 2020 with subsidiaries of Merck & Co. Inc., Kenilworth, N.J., USA (“Merck”), known as MSD outside the United States and Canada. As a result, Nabriva expects to recognize 100% of net product sales of SIVEXTRO in its results of operations beginning on April 12, 2021. SIVEXTRO is an oxazolidinone-class antibacterial indicated in adults and pediatric patients 12 years of age and older for the treatment of acute bacterial skin and skin structure infections (ABSSSI) caused by certain susceptible Gram-positive microorganisms.

Under the terms of the agreement with Merck & Co. Inc., Kenilworth, N.J., USA, Nabriva will continue to procure SIVEXTRO from Merck & Co. Inc., Kenilworth, N.J., USA and be solely responsible for marketing, sales, and distribution of SIVEXTRO in the United States at least through December 31, 2023, with renewable three-year extensions.

To provide community-based commercial and sales services for SIVEXTRO and XENLETA in the United States, Nabriva entered into an agreement with Amplity Health, a leading pharmaceutical contract commercial organization, in July 2020.

About SIVEXTRO^® (tedizolid phosphate)

SIVEXTRO was approved by the U.S. Food and Drug Administration in 2014. It is indicated in adults and pediatric patients 12 years of age and older for the treatment of acute bacterial skin and skin structure infections (ABSSSI) caused by susceptible isolates of the following Gram-positive microorganisms: Staphylococcus aureus (including methicillin-resistant (MRSA) and methicillin-susceptible (MSSA) isolates), Streptococcus pyogenes, Streptococcus agalactiae, Streptococcus anginosus group (including Streptococcus anginosus, Streptococcus intermedius and Streptococcus constellatus), and Enterococcus faecalis. To reduce the development of drug-resistant bacteria and maintain the effectiveness of SIVEXTRO and other antibacterial drugs, SIVEXTRO should be used only to treat ABSSSI that are proven or strongly suspected to be caused by susceptible bacteria. When culture and susceptibility information are available, they should be considered in selecting or modifying antibacterial therapy. In the absence of such data, local epidemiology and susceptibility patterns may contribute to the empiric selection of therapy.

MRSA has been categorized by the U.S. Centers for Disease Control and Prevention (CDC) as a serious public health threat.¹ SIVEXTRO 200 mg is administered once daily orally or as an intravenous (IV) infusion over one hour for six days.

Selected Important Safety Information for SIVEXTRO

Patients with neutropenia: The safety and efficacy of SIVEXTRO in patients with neutropenia (neutrophil counts <1000 cells/mm³) have not been adequately evaluated. In an animal model of infection, the antibacterial activity of SIVEXTRO was reduced in the absence of granulocytes. Alternative therapies should be considered when treating patients with neutropenia.

Clostridioides difficile–associated diarrhea (CDAD), ranging from mild diarrhea to fatal colitis, has been reported with nearly all systemic antibacterial agents, including SIVEXTRO. Evaluate all patients who present with diarrhea following antibacterial drug use. Careful medical history is necessary because CDAD has been reported to occur more than two months after the administration of antibacterial agents. If CDAD is suspected or confirmed, antibacterial use not directed against C. difficile should be discontinued, if possible.

Development of drug-resistant bacteria: Prescribing SIVEXTRO in the absence of a proven or strongly suspected bacterial infection or prophylactic indication is unlikely to provide benefit to the patient and increases the risk of the development of drug-resistant bacteria.

Adverse reactions: The most common adverse reactions (≥ 2%) in adults for SIVEXTRO are nausea (7%), headache (5%), diarrhea (4%), vomiting (3%), and dizziness (2%).

In adult patients receiving SIVEXTRO intravenously, infusion- or injection-related adverse reactions including but not limited to: phlebitis, injection- or infusion-site pain or swelling, injection-site reaction, erythema, or induration, and infusion-related reaction occurred (4%).

The most common adverse reactions (>2%) in pediatric patients 12 years of age and older are phlebitis (3%) and increased hepatic transaminases (3%).

Drug interactions with BCRP substrates: SIVEXTRO (when administered orally) can increase the plasma concentrations of orally administered Breast Cancer Resistance Protein (BCRP) substrates and the potential for adverse reactions. Monitor for adverse reactions related to the concomitant BCRP substrates if coadministration cannot be avoided.

About Nabriva Therapeutics plc

Nabriva Therapeutics is a biopharmaceutical company engaged in the commercialization and development of innovative anti-infective agents to treat serious infections. Nabriva Therapeutics received U.S. Food and Drug Administration approval for XENLETA^® (lefamulin injection, lefamulin tablets), the first systemic pleuromutilin antibiotic for community-acquired bacterial pneumonia (CABP). Nabriva Therapeutics is also developing CONTEPO™ (fosfomycin) for injection, a potential first-in-class epoxide antibiotic for complicated urinary tract infections (cUTI), including acute pyelonephritis. Nabriva entered into an exclusive agreement with subsidiaries of Merck & Co. Inc., Kenilworth, N.J., USA to market, sell and distribute SIVEXTRO^® (tedizolid phosphate) in the United States and certain of its territories.

Forward-Looking Statements

Any statements in this press release about future expectations, plans and prospects for Nabriva Therapeutics, including but not limited to statements about the potential benefits to Nabriva Therapeutics under its sales promotion and distribution agreement with the subsidiaries of Merck & Co. Inc., Kenilworth, NJ, USA the potential benefits to patients of SIVEXTRO and XENLETA, the market opportunity for SIVEXTRO and XENLETA, the availability of SIVEXTRO through major U.S. specialty wholesalers, the impact on Nabriva Therapeutics’ reported revenue from anticipated sales of SIVEXTRO, the sufficiency of its cash resources and other statements containing the words “anticipate,” “believe,” “estimate,” “expect,” “intend,” “may,” “plan,” “predict,” “project,” “target,” “potential,” “likely,” “will,” “would,” “could,” “should,” “continue,” and similar expressions, constitute forward-looking statements within the meaning of The Private Securities Litigation Reform Act of 1995. Actual results may differ materially from those indicated by such forward-looking statements as a result of various important factors, including: Nabriva Therapeutics ability to satisfy the conditions under the distribution agreement to obtain the right to exclusively distribute and promote SIVEXTRO, including its ability to establish or secure a commercial infrastructure sufficient to promote and distribute SIVEXTRO, the extent of business interruptions resulting from the infection causing the COVID-19 outbreak or similar public health crises, the ability to retain and hire key personnel, the availability of adequate additional financing on acceptable terms or at all and such other important factors as are set forth in Nabriva Therapeutics’ annual and quarterly reports and other filings on file with the SEC. In addition, the forward-looking statements included in this press release represent Nabriva Therapeutics’ views as of the date of this press release. Nabriva Therapeutics anticipates that subsequent events and developments may cause its views to change. However, while Nabriva Therapeutics may elect to update these forward-looking statements at some point in the future, it specifically disclaims any obligation to do so. These forward-looking statements should not be relied upon as representing Nabriva Therapeutics’ views as of any date subsequent to the date of this press release.

Please see Prescribing Information for SIVEXTRO^® (tedizolid phosphate) at https://www.merck.com/product/usa/pi_circulars/s/sivextro/sivextro_pi.pdf

CONTACTS:

For Investors

Kim Anderson

Nabriva Therapeutics plc

ir@nabriva.com

For Media

Mike Beyer

Sam Brown Inc.

mikebeyer@sambrown.com

312-961-2502

¹ CDC’s Antibiotic Resistance Threats in the United States (2019 AR Threats Report) accessed 4/13/2021 https://www.cdc.gov/drugresistance/biggest-threats.html#mrsa